Light emitting diode lighting device

Abstract

The present invention relates to a light emitting diode (LED) lighting device ( 10 ). The lighting device comprises a light guide plate ( 12 ), and a plurality of LEDs ( 16 ) accommodated in holes ( 14 ) arranged in the plane of the light guide. At least one hole has a first side facet ( 18 ) for coupling light from any LED in the hole into the light guide and a second opposite side facet ( 20 ) for coupling light out of the light guide. Further, the holes are arranged such that all first side facets are facing one direction. Such an LED based lighting device can be made thin and unobtrusive.

The invention claimed is: 
     
       1. A light emitting diode (LED) lighting device, comprising:
 a light guide plate, and 
 a plurality of LEDs accommodated in holes arranged in the plane of the light guide, wherein at least one hole has a first side facet for coupling light from any LED in the hole into the light guide and a second opposite side facet for coupling light out of the light guide, and wherein the holes are arranged such that all first side facets are facing one direction, wherein the holes are arranged in the plane of the light guide according to a staggered distribution. 
 
     
     
       2. A device according to  claim 1 , wherein at least one second opposite side facet is reflective and tilted in relation to the plane of the light guide. 
     
     
       3. A device according to  claim 1 , wherein side walls of the holes between the first and second opposite side facets are adapted to reflect any incoming light. 
     
     
       4. A device according to  claim 1 , wherein the light guide has a thickness of about 3 mm or less. 
     
     
       5. A device according to  claim 1 , wherein the holes are arranged in the staggered formation including a first row and a second row adjacent to the first row such that light in-coupled from the first row of holes does not hit the second opposite side facet of the at least one hole in the second row of holes. 
     
     
       6. A device according to  claim 1 , wherein at least one LED comprises a collimator. 
     
     
       7. A device according to  claim 1 , wherein at least one hole has an integrated collimator. 
     
     
       8. A light emitting diode (LED) lighting device, comprising:
 a light guide plate, and 
 a plurality of LEDs accommodated in holes arranged in the plane of the light guide, wherein at least one hole has a first side facet for coupling light from any LED in the hole into the light guide and a second opposite side facet for coupling light out of the light guide, and wherein the holes are arranged such that all first side facets are facing one direction, wherein at least one LED comprises a collimator. 
 
     
     
       9. A device according to  claim 8 , wherein at least one second opposite side facet is reflective and tilted in relation to the plane of the light guide. 
     
     
       10. A device according to  claim 8 , wherein side walls of the holes between the first and second opposite side facets are adapted to reflect any incoming light. 
     
     
       11. A device according to  claim 8 , wherein the light guide has a thickness of about 3 mm or less. 
     
     
       12. A light emitting diode (LED) lighting device, comprising:
 a light guide plate, and 
 a plurality of LEDs accommodated in holes arranged in the plane of the light guide, wherein at least one hole has a first side facet for coupling light from any LED in the hole into the light guide and a second opposite side facet for coupling light out of the light guide, and wherein the holes are arranged such that all first side facets are facing one direction, wherein at least one hole has an integrated collimator. 
 
     
     
       13. A device according to  claim 12 , wherein at least one second opposite side facet is reflective and tilted in relation to the plane of the light guide. 
     
     
       14. A device according to  claim 12 , wherein side walls of the holes between the first and second opposite side facets are adapted to reflect any incoming light. 
     
     
       15. A device according to  claim 12 , wherein the light guide has a thickness of about 3 mm or less.